Git Hooks and CSS Preprocessors

By  on  

For one of my recent projects, I've decided to use Stylus.  I'm accustomed to using Sass but that would require adding Ruby to our stack -- Stylus is Node.js-based, and since I'm already using Node.js for a few other tasks, I thought I'd give Stylus a try.  Since I'm heavily developing the front-end of the project, I'm either fixing bugs or creating new features, all of which requires heavy CSS edits.  The problem I'm running into is that I'm forgetting to reprocess stylesheets when I switch branches, so pages start to look funky and I start having heart attacks.

Seeing as my memory is faulty, I've been looking for an automated solution to this problem.  Stylus has a "watch" feature but I've found it slow and I'm impatient.  Next I turned to git hooks.  I've always heard about them but never spent much time with them -- big mistake.  To solve my branch-switching, preprocessor blues, I created a post-checkout hook.  Bang!

The first step is placing a file called post-checkout (no extension) in the project's .git/hooks directory:

cd .git/hooks && touch post-checkout

Next up is running my compile script.  The compile script is an external file (it's hooked into our build process) so all I need to do is run it:

#!/bin/sh
./scripts/compile-scripts

In case you want to see my CSS compile script, here it is:

#!/bin/sh

BASEDIR=$(dirname $0)
CSSDIR=$BASEDIR/../media/redesign/css/

if [ ! -d "$CSSDIR" ]; then
	mkdir $BASEDIR/../media/redesign/css/
fi

for file in main print wiki demo-studio profile search zones home
do
	stylus $BASEDIR/../media/redesign/stylus/$file.styl --out $BASEDIR/../media/redesign/css --compress
done

I probably don't need to tell you how awesome git hooks are, but in the case of instant CSS preprocessing, git hooks are a big help!

Recent Features

  • By
    Page Visibility API

    One event that's always been lacking within the document is a signal for when the user is looking at a given tab, or another tab. When does the user switch off our site to look at something else? When do they come back?

  • By
    I’m an Impostor

    This is the hardest thing I've ever had to write, much less admit to myself.  I've written resignation letters from jobs I've loved, I've ended relationships, I've failed at a host of tasks, and let myself down in my life.  All of those feelings were very...

Incredible Demos

  • By
    5 More HTML5 APIs You Didn’t Know Existed

    The HTML5 revolution has provided us some awesome JavaScript and HTML APIs.  Some are APIs we knew we've needed for years, others are cutting edge mobile and desktop helpers.  Regardless of API strength or purpose, anything to help us better do our job is a...

  • By
    MooTools Typewriter Effect Plugin

    Last week, I read an article in which the author created a typewriter effect using the jQuery JavaScript framework. I was impressed with the idea and execution of the code so I decided to port the effect to MooTools. After about an hour of coding...

Discussion

  1. I think you might be doing it the hard way :) If you’re on node.js, use grunt tasks for these compiling on the fly workflow. Check out my boilerplate’s grunt tasks: https://github.com/constantx/basement

  2. Hichem

    That’s awesome constantx , that might be a good idea for another blog post i think :)

  3. Small caveat: The hook script must be executable for git to recognize it:

    chmod +x .git/post-checkout
  4. Carl

    Nice! Hopefully there is something similar for my git workflow. I have one main develop branch and several different branches (projects) in which i usually merge the changes from the develop branch. After a merge in each of the project branches my sass build script should be running and create the individual project styles. But it should only be dine if there are no merge conflicts.
    I know there is a merge hook but how can i be sure there merge was conflict free?

  5. Thanks for sharing! For a moment I’ve wondered how you handle your processed CSS files if you generate them only after checkout… but I guess you don’t version control them, then.

    We keep our generated files in version control and that’s why I’ve put the compilation step in a pre-commit hook. But yes, I’ve also found git hooks the way to go here :-)

Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!